Fujitsu Corporation

Kabushiki Kaisha Ace Denken

Takaharu Nakamura

Kazuo Kawabata

Kazuhisa Obuchi

Tetsuya Yano

Nobuhisa Aoki

Takayoshi Ode

Hiroaki Iwamoto

Takeshi Takano

Kazuhisa Ohbuchi

Takatoshi Takemoto

Kazunari Kawashima

Hideyuki Kadomatsu

Yukio Takeda

Moriyuki Aoyama

Yoshiharu Tajima

Hajime Hamada

Yasuyuki Oishi

Shunji Miyazaki

Kenji Suda

Yoshiaki Kaneko

Syuuichi Murata

Eiji Itaya

Akihiko Kimura

Yasunobu Watanabe

A radio communication system including: a first and second base station apparatuses which include one or more of sells or sectors respectively; and a terminal apparatus, wherein the first and second base station apparatuses and the terminal apparatus performs radio communication, the first and second base station apparatuses includes: a process unit which performs a scrambling process to a first and second transmission data respectively by using a common scrambling code when the first and second transmission data differing each of the cells or the sectors are transmitted to the terminal apparatus; and a transmission unit which transmits the scrambling processed first and second transmission data to the terminal apparatus respectively, and the terminal apparatus includes a reception unit which receives the first and the second transmission data and performs descrambling process to the first and the second transmission data by using the common scrambling code.

Radio communication system, base station apparatus, terminal apparatus, and radio communication method in radio communication system

A mobile terminal having a receive diversity function using a plurality of receive antennas, having a calculation section which combines respective level measurement results of the receive antennas and calculates a level measurement value after being combined as the level measurement result of the mobile terminal.

Mobile terminal based on W-CDMA system having receive diversity function and system thereof

A communications system includes a first reception device and a transmission device. The transmission device includes a modulator operable to modulate a plurality of subcarriers using a signal series obtained by multiplexing a first signal series to be transmitted to the first reception device and a second signal series to be transmitted to a plurality of reception devices including the first reception device in a communications area of the transmission device and a transmitter operable to transmit the modulation signals. The first reception device includes a demodulator operable to regenerate the first signal series and the second signal series.

Transmission delay utilizing orthogonal frequency division multiplex transmission method

A radio communication system including: a base station; a terminal; and a relay station, wherein the base station and the terminal perform radio communication via the relay station, the base station includes: a change unit which changes at least any of a radio resource allocation method for the relay station and the terminal, the radio resource allocation method and a scheduling method, or the radio resource allocation method, the scheduling method and a relay method in the relay station; and a transmission unit which transmits a change notice for notifying the relay station of the change by the change unit, the relay station includes a reception unit which receives the change notice, and the base station, the relay station, and the terminal perform radio communication using at least the radio resources allocating or allocated by the radio resource allocation method after the change.

Radio communication system, base station apparatus, terminal apparatus, relay station apparatus and radio communication method for radio communication system

A transmission method includes transmitting a signal using an orthogonal frequency division multiplexing, receiving the transmitted signal at a plurality of reception devices, and controlling a transmission power for first signals transmitted to the plurality of reception devices in an area formed by the transmitter to be greater than a transmission power for second signals transmitted to a specific device in the area, wherein said first signals and said second signals are time division multiplexed.

Orthogonal frequency division multiplex transmission method

In an apparatus such as a turbo decoding apparatus in which it is necessary to carry out interleave operation and deinterleave operation, there are provided a memory unit () and a memory control unit () capable of changing data writing order and data reading order with respect to the memory unit () depending on whether data is to be interleaved or deinterleaved. With this arrangement, the single unit of memory () can function as an interleaver and a deinterleaver, thereby reducing the size and cost the device.

Turbo decoding apparatus and interleave-deinterleave apparatus

A system and apparatus including a mobile station for use in a spread communication system having a spread signal on a particular channel for establishing synchronization. The particular channel for establishing synchronization existing on a plurality of frequencies. The mobile station includes a receiving unit receiving the plurality of frequencies; a measuring unit measuring a strength or a correlation value of the spread signal of the particular channel for each of the plurality of frequencies received by said receiving unit; and a synchronization establishing unit establishing synchronization based on the measured strength or correlation value of the spread signal.

Spread communication system and mobile station thereof

Disclosed are an error-detecting encoding apparatus for creating parity bits by error-detecting encoding processing, appending the parity bits to an input data string and encoding the data string, and an error-detecting decoding apparatus for detecting error using these parity bits. Data segmenting means segments an input data string, which is to undergo error-detecting encoding, into a plurality of sub-data strings, dividing means divides the segmented sub-data strings by a polynomial, which is for generating an error-detecting code, and calculates remainders, converting means applies conversion processing, which conforms to a segmentation position of the sub-data strings, to the remainders on a per-remainder basis, and combining means combines converted values, which have been obtained by the conversion processing, and outputs parity bits. An encoder appends this parity to a data string, and a decoder detects error using this parity.

Error-detecting encoding and decoding apparatus and dividing apparatus

In a mobile communication system for authenticating a communicating party when communication is performed between a mobile terminal and a device on the side of a network, the mobile terminal, upon receiving a request signal requesting operation execution from the network device, sends the network device an authentication request signal in order to determine whether the request signal is a request signal from an authorized network device, and performs an authentication operation. The network device executes an authentication operation based upon the authentication request signal received from the mobile terminal and sends a result of the authentication operation to the mobile terminal. The mobile terminal compares the result of its own authentication operation and the result of the authentication operation sent from the network device and executes an operation that is in accordance with the request signal only if authentication that the network device is an authorized network device is obtained based upon agreement of results.

Mobile communication system and apparatus constituting same

A search circuit in a CDMA system which has a plurality of base stations respectively employing different carrier frequencies, the search circuit selects one carrier frequency among the different carrier frequencies to perform a cell search of the one carrier frequency. The search circuit includes a first search unit searching a plurality of carrier frequencies of the DS-CDMA system; and a controller selecting a highest strength or highest correlation value carrier frequency among the plurality of carrier frequencies based on a result of the first search unit, setting the selected carrier frequency as the one carrier frequency among the different carrier frequencies to perform the cell search of the one carrier frequency. A mobile station adopting the search circuit includes a three-stage cell search process.

A transmission circuit transmits a connection request including a 'signature' to a base station. The demodulator demodulates the AICH for transmitting a notification corresponding to the connection request. When requested communications are enabled, the AICH transmits the 'signature'. A multiplier multiplies a demodulation signal by the &#x201c;signature&#x201d;. A voltage computation unit converts the output of the multiplier into a voltage value. An integrator integrates the voltage value computed by the voltage computation unit for each received symbol for the respective symbols corresponding to the &#x201c;signature&#x201d;. A threshold generation unit adaptively selects one of a threshold determined based on the noise of a transmission path or a threshold determined based on the receiving power. If the output of the integrator is larger than the selected threshold, it is determined that the communications have been enabled.

Apparatus and method for discriminating information transmitted using radio signal

A system including base stations and a mobile station that performs a three-stage cell search process. Each base station includes a transmission unit using at least one carrier frequency for transmitting a perch channel signal, in which the at least one carrier frequency is uniquely distinguishable from carrier frequencies used by other base stations. The mobile station performs a first-stage search of the three-stage cell search and represents a search of a plurality of carrier frequencies; performs a second-stage search of the three-stage cell search and represents a search of a specified carrier frequency; performs a third-stage search of the three-stage cell search and represents a search of said specified carrier frequency; and includes a controller selecting the highest strength or highest correlation value carrier frequency among the carrier plurality of carrier frequencies based on a result of the first-stage search to set the selected carrier frequency as said specified carrier frequency.

An interleaving apparatus comprises a first storing unit for storing data to be transmitted and a first control unit for controlling the first storing unit so that the data to be transmitted is outputted from the first storing unit with the data to be transmitted arranged in a matrix and at least either columns or rows of the data to be transmitted randomly rearranged, facilitating the interleaving. The result is that biased distribution of data, which leads to degradation of the transmission quality, can be prevented relatively easily in a simple structure.

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Kawasaki, Japan

Takaharu Nakamura